Recent content by rwx

Thanks, Dirk -- good suggestion

Update -- I am collecting heat loss data on a pool at a rental house that I have. It is exposed directly to the wind, which has been relatively high for the last few days. Preliminary data shows that there needs to be some changes made to account for higher wind conditions (which are much...

Just look at the bill where you ran the heater, and divide the total bill by the CCF.

using your dimensions, $1.23 per CCF, .85 heater efficiency, 20 degree rise for initial heating and 20 degrees temperature differential, I get: $53.63 to heat the pool $1.29 per hour maintain the temperature. However, the high cost may have to do with the cost of gas, which depends on how you...

Thanks for the data. I'm trying to duplicate your calculation. Is the pool surface area the sum of the 16x31 and 11x7? (the calc for heating the pool to temperature uses the pool volume, and the calc for heat loss per hour uses pool surface area)

To Catanzaro Although I came out with a result about the same as your data sheet (I calculated 6 degrees pool temp increase in 6.8 hours with a 117,000 BTU per hour input), I think when you get into the technical details there are some environmental effects that probably cancel each other out...

The intent of this was to provide a simplified calculation to estimate the times and costs to heat a pool over an extended period, like a week or a month. It's true that the heat loss coefficient is the result of a lot of variables -- I have seen values as low as 4 and as high as 10.5, so the...

To: Catanzaro Thanks for providing all the data in your link. If you can give me the pool dimensions, I can re-calculate the pool volume. It did show that I should include the cooling effect in the calculation, and that heat pumps are rated in BTU output, where gas heaters are rated in BTU input.

Your heat pump rating is too low. I don't have one, but most of them are 100,000 - 150,000 BTU per hour, and with a heat pump you have to look at the COP for the ambient temperature. I'll be happy to do some research for you -- what is the heat pump model number, and your pool dimensions...

You are right, there are a lot of variables that can affect the energy calculation, but I boiled it down to simplify the calculation. Although have not taken the data you have, I know the energy required to heat the pool is pretty accurate. WRT the energy required to maintain the...

For Excel users who do not want to open the .xls file, here is the same thing in a text file that can be imported into a clean Excel file. It is tab delimited. I will also write this up showing the formulas.

I can write it up in text, and I think I can put the Excel formulas in a .txt file that can be imported into Excel.

I had some friends ask me about the cost to heat and maintain temperature for a pool. I made up the attached Excel spreadsheet to estimate the cost to initially heat a pool, and the cost to maintain the heat. It's basically fill in the appropriate blanks in column A, and the results appear in...

Emailed Raypak, and got a response withing an hour -- suggested I check the voltage to the board (which was good). I got a new board, installed it today, and everything works again.

I have a 266 with electronic ignition, but the spark is too weak to ignite the gas (I can easily light it with a match). I pulled out the PC board, removed the high tension wire and tried another wire held close to the sheet metal and the spark was still weak. Is this a PC board issue?